A kind of synthetic method of 4,4'-diaminodiphenyl ether

Abstract

The invention discloses a synthetic method of 4, 4'-diaminodiphenyl ether. The synthetic method comprises the following steps: S1, nitrosation reaction: adding sodium nitrite and diphenyl ether into awater phase, slowly dropwise adding hydrochloric acid in a range of 0-5 DEG C till the reaction is finished, separating out crystals, filtering the crystals, and drying the crystals in vacuum to obtain 4, 4'-diaminodiphenyl ether, wherein the reaction process is as follows; and S2, reductive reaction: adding the obtained solid into a high pressure kettle, adding a catalyst by taking alcohol as asolvent, pressurizing hydrogen to 0.5-4 MPa, heating and stirring the mixture to 70-120 DEG C, and keeping the temperature for 2-6 hours to obtain 4, 4'-diaminodiphenyl ether. The synthetic method disclosed by the invention can reduce the production cost, reduce the environmental pollution, improve the safety coefficient and reduce the emission of three wastes.

Description

technical field [0001] The invention relates to the synthesis of fine chemical intermediates, in particular to a synthesis method of 4,4'-diaminodiphenyl ether. Background technique [0002] ODA (4,4'-diaminodiphenyl ether) is an important fine chemical intermediate, mainly used as a raw material for the production of polyimide resin, polyamide resin, epoxy resin and other products, while 4,4 '-Diaminodiphenyl ether can also be used as a cross-linking agent, and can also be used to replace carcinogenic benzidine to produce azo dyes and reactive dyes. [0003] At present, there are mainly four routes for the synthesis of ODA, namely: ① p-dinitrobenzene method, ② diphenyl ether nitration method, ③ p-nitrochlorobenzene and p-nitrophenol condensation method, ④ p-nitrochlorobenzene one-step condensation method legitimate. The raw materials in method ① are volatile and highly toxic, and cause great environmental hazards. Method ② The by-products are abundant and the yield is lo...

AI Technical Summary

Problems solved by technology

Method ② more by-products and lower yield

Strong corrosiveness and great environmental pollution

Routes ③ and ④ are two routes commonly used in industrial production at present, but these two routes have higher requirements on equipment. To synthesize nitro compounds, concentrated sulfuric acid is used as a solvent, and the dosage is large. After the reaction, a large amount of water needs to be added for dilution. The target product is separated and a large amount of strongly acidic wastewater is produced, and there are many three wastes

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